Dynamic Conformal Neural Electroactive Biointerfacing Sustains Bioelectronic Coupling for Spinal Cord Repair

Stable bioelectronic coupling in mechanically active tissues remains challenging because conventional interfaces rely on static architectures that cannot dissipate deformation-induced interfacial stress, resulting in progressive contact failure and signal instability. Here, we report an injectable magnetoelectric hydrogel that forms a dynamic conformal neural electroactive tissue-biointerface (DyCONNECT) with deformable neural tissues. By integrating polydopamine-modified magnetoelectric nanoparticles within a dynamically adaptive conductive network, DyCONNECT combines tissue adhesion, electrical conductivity, structural recoverability, and wireless electroactive regulation. The dynamic network enables continuous stress relaxation and interfacial reconfiguration, allowing DyCONNECT to preserve conformal tissue contact, suppress deformation-induced damage accumulation, and maintain low-impedance electrical coupling under cyclic mechanical loading. Upon pulsed magnetic stimulation, DyCONNECT generates localized electrical cues that enhance neural-related cellular activities and evoke remote electrophysiological responses. In a rat spinal cord injury model, DyCONNECT facilitates neuronal preservation, axonal regeneration, and sensorimotor functional recovery. These results demonstrate that dynamic interfacial adaptation can preserve bioelectronic coupling under physiological deformation and support electroactive neural repair in mechanically active tissues.